Guerra-Hernández NE, Camargo-Muñiz MD, Antón-Hernández L, Luis-Yanes MI, García-Nieto VM

Language: Spanish
References: 17
Page: 13-18
PDF size: 249.20 Kb.

ABSTRACT

Introduction. The posterior urethral congenital valves are mucosal folds in the posterior urethra that occur only in male patients. They are the most common cause of urinary tract obstruction in the neonatal period. Due to hyper pressure that begins in the urinary bladder, it is highly frequent for these to come together with bilateral vesico-ureteral reflux. In some cases, this reflux is unilateral and is associated with posterior urethral valve and renal dysplasia (VURD syndrome). A better long-term renal outcome in these cases has been reported. Nevertheless, there is very little experience regarding prognosis of the remaining group of children without reflux.
Methods. We studied 4 children with posterior urethral valves and lack of vesico-ureteral reflux with controlled follow-up during 3 and 6 years. We described disease presentation and clinical course from diagnosis, surgical intervention, renal function, radiologic features, N-acetylglucosaminidase (NAG), and microalbuminuria during follow-up.
Results. Renal glomerular function is normal in all 4 cases. Only one patient had a mild default in urinary concentration capacity and a slight increase in urinary elimination of N-acetylglucosaminidase.
Conclusion. Medical and surgical management of the posterior urethral valves has improved long-term renal outcome in these patients. Lack of vesico-ureteral reflux, urinary ascites, urinary extravasation, and large congenital bladder diverticula can serve as a pop-off mechanism to buffer hyperpressure in the urinary tract, leading to the preservation of improved renal function in boys with posterior urethral valves.

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